Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Finite-lived Intangible Assets [Roll Forward]
CDI and CRI Balance, beginning of period	$ 119,497	$ 119,497	$ 64,187	$ 119,497	$ 64,187
Accumulated Amortization, beginning of period	(46,217)	(39,871)	(30,885)	(39,871)	(27,821)
Amortization	(5,587)	(6,346)	(3,065)	(11,933)	(6,129)
Fully amortized portion	0	0	0	0
CDI and CRI Balance, end of period	119,497	119,497	64,187	119,497	64,187
Accumulated Amortization, end of period	(51,804)	(46,217)	(33,950)	(51,804)	(33,950)
Net CDI and CRI, end of period	67,693	73,280	30,237	67,693	$ 30,237
CDI and CRI
Finite-lived Intangible Assets [Roll Forward]
Fully amortized portion	$ 0	$ 0	$ 0	$ 0

Finite Lived Intangible Assets Fully Amortized Portion

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Details

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